Audio-visual instructional system with synchronized visual and audio presentations

ABSTRACT

An audio-visual instructional system wherein the student or trainee is simultaneously subjected to synchronized visual and audio presentations for conditioning the trainee by utilizing both sensory perceptions. The system includes a visual display which is actuated by a memory device which is in turn actuated by a control signal of a signal reproducing means.

United States Patent Tishman [451 Apr. 4, 1972 [54] AUDIO-VISUALINSTRUCTIONAL SYSTEM WITH SYNCHRONIZED VISUAL AND AUDIO PRESENTATIONS[72] Inventor: Abraham Tishman, Greenbelt, Md.

[73] Assignec: Dynamic Typing, Inc., Washington, DC.

[22] Filed: Dec. 20, 1968 [21 Appl. No.: 785,600

[52] US. Cl. ....340/I72.5, 35/6 [51 Int. Cl. ..G09b 13/02 [58] Field 0!Search ..340/l72.5, 324, 334, 366; 235/i57; 35/6, 8, 35 C; 40/28.];178/56,

[56] Reierences Cited UNITED STATES PATENTS 2,780,679 2/1957Vandivere,.lr ..340/l72.5X

MEMORY COUNTER l] i MEM ORTA DECODER 2,985,069 5/l96l Sampson ..353/l53,245,156 4/1966 De Bloois et al 3,340,524 9/1967 Rinaldi 3,414,98512/1968 Ashley ..35/8

Primary Examiner-Raulfe B. Zache Assistant Examiner-Melvin B. ChapnickAuorney0berlin, Maky, Donnclly & Renner 5 7] ABSTRACT An audio-visualinstructional system wherein the student or trainee is simultaneouslysubjected to synchronized visual and audio presentations forconditioning the trainee by utilizing both sensory perceptions. Thesystem includes a visual display which is actuated by a memory devicewhich is in turn actuated by a control signal of a signal reproducingmeans.

18 Claims, 4 Drawing Figures Patented April 4, 1972 3,654,619

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42 CHANNEL I I 36 INVENT OR ABRAHAM T/SHMA/V ahww m ATTORNEYSAUDIO-VISUAL INSTRUCTIONAL SYSTEM WITH SYNCI-IRONIZED VISUAL AND AUDIOPRESENTATIONS BACKGROUND OF THE INVENTION The present invention relatesas indicated to an audio-visual instructional system, with the terminstructional" as used herein being employed in its broadest sense toinclude systems primarily intended to facilitate the learning process,for example, in a typical classroom environment supplementing teacherinstruction, or in a system designed primarily to condition the trainee,that is, to increase the reflex action of the trainee. An example of aconditioning type system is the training or teaching of keyboardinstruments, such as typewriters, such system having the capability ofaccomplishing such training without the presence of a teacher orinstructor. It should be understood, and it will become apparenthereinbelow, that the system of the present invention has directapplication to both systems described, and to practically anyenvironment where synchronous audio and visual presentation is desired.

It has long been recognized that the learning or training process can besignificantly enhanced by audio or visual aids. A common audio teachingaid comprises programmed magnetic tapes on which are carried entireprograms which are delivered to the trainees on playback, either througha central loudspeaker or through individual headphones used by eachtrainee. Known visual aids include movie or slide projecting devices or,for keyboard instruments, suitable display boards. For typewritertraining, a known display board is in the form of a replica of atypewriter keyboard, with the board being wired for predeterminedactuation, in accordance with the lesson, to illuminate individualletters or symbols on the replica keyboard individually and in sequence,according to the particular lesson.

Training systems for keyboard instruments have been developed whichsynchronously present both visual and audio lesson segments to thetrainee thereby making more effective the training process. However,heretofore, these synchronous visual and audio systems have normallyemployed magnetic tape for producing both the audio and the visualpresentations. A conventional two-track magnetic tape is used, one trackbeing adapted to carry the audio portion of the program, and the secondtrack comprising a signal track adapted to carry impulse signals foractuating synchronously the visual aid. The signal track mustnecessarily carry impulse signals that are capable of discriminatingactuation of the visual aid so that the visual presentation issynchronous with the audio track, with such discrimination beingaccomplished by providing a different frequency tone for every letter orsymbol to be contained in the lesson. As a result, programming thevisual presentation is more difficult and the varying frequencyrequirements are a practical deterrent on the number of letters orsymbols contained in a particular lesson. This limitation isparticularly significant in the teaching of instruments having a greatmany more letters, symbols or the like than a conventional typewriter.

In present magnetic tape systems, size and cost have been seriousdetractions. The cost per installation has been relatively high, and thesize of the equipment has dictated, for esthetic reasons, the locationof the visual display apart from the other system components.

SUMMARY OF THE INVENTION memory device in turn actuating the visualdisplay to achieve the simultaneous presentation. The system includesmeans for decoding the memory input and output signals, and further includes means for selecting the proper memory, where more than one memoryis present in the system, and disabling the other memories.

Another object of the present invention is to provide a system which isadapted to be contained entirely within the visual display, thereby toprovide an esthetically attractive design.

Still another object of the present invention is to provide aself-contained system as described which is unusually light in weightthereby to facilitate handling and installation thereof.

Yet another object of the present invention is to provide a system whichis simple to operate. As noted, the system is selfcontained, and thesystem is conditioned for operation by plugging the power cord into aconventional wall outlet.

A still further object of the invention is to provide a system of thetype described that can be manufactured at relatively low cost and whichis substantially devoid of maintenance problems.

A further object of the invention is to provide a system that does notrequire an actuating code, after the initial frequency tone has selectedthe desired memory.

Reference is now made to the application drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a perspective view of atypical installation of the present invention, showing two traineesreceiving the synchronized audio and visual presentation;

FIG. 2 is a schematic drawing, partially in block diagram form, of thesystem;

FIG. 3 is a schematic drawing of the memory portion of the system, and

FIG. 4 is a schematic drawing of the preferred recording and reproducingmeans of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now in more detail tothe drawings, wherein like parts are indicated by like referencenumerals, and initially to FIG. I, there is illustrated therein atypical installation of the system of the present invention, with theentire system being contained within a housing generally indicated at 10adapted to be suspended or otherwise mounted on wall 12. As shown, thehousing 10 is mounted at a suitable height to afford optimum viewingthereof by the students or trainees S.

A display panel 14 is mounted at the front of the housing It], with thepanel preferably being mounted for movement relative to the housing, forexample, by means of hinges 16, to permit the panel to be swung upwardlyto obtain access to the interior of the housing and the systemcomponents.

A pair of speakers l8, only one of which is visible in FIG. I, aremounted in the respective sidewalls 20 of the housing, and a taperecorder generally indicated at 24 is mounted in one of the sidewalls 20relatively adjacent the bottom thereof, with the top and front of therecorder being exposed exteriorly of the housing to facilitateinstallation and removal of the tape cassettes from the recorder. Thetape recorder is preferably of conventional construction, and can bepurchased commercially from any number of suppliers. A power cord 26 ispro vided which in the form shown extends from sidewall 20 and isadapted to be plugged into a conventional wall outlet, as shown at 28,for operating the system. A carrying handle 30 is mounted on the topwall of the housing 10 to facilitate handling of the same. The housing10 is preferably made of light weight material, for example aluminum,thereby greatly facilitating shipping and installation of the system. Inaddition, the entire system is self-contained in the housing 10 and canbe conditioned for operation simply by connecting the cord to a walloutlet.

Each student or trainee S is provided with a typewriter commonlydesignated at 32. Although the audio could be supplied entirely throughthe speakers 18, each student may if desired be provided with a set ofheadphones commonly designated at 34 to receive the audio portion of thelesson. As noted above and as will be pointed out in more detailhereinbelow, the audio lesson is synchronized with the visualpresentation which, for typewriter training, comprises narrativeinstruction synchronized with predetermined actuation of the visualdisplay.

In the form shown, the panel [4 represents the keyboard of a typewriterand is, in fact, an exact replica of the samev Each letter or symbolcontained on the typewriter keyboard is likewise shown on the panel 14.Each symbol on the panel I4 has associated therewith illuminating means,such as a lamp or bulb, for illuminating the letter or symbol, asprogrammed and synchronized with the lesson narrative. For example, thestudent may be instructed to type "a at the same time the letter 11" isilluminated on the panel 14.

It should be clearly understood that the illustrated environ mentrepresents but one of many uses of the present invention. The system isadaptable to the training of essentially all types of keyboardinstruments, such as organs, pianos and the like, or practically anylearning or conditioning environment where simultaneous audio and visualpresentations are feasible for optimum teaching results. Thus, the basicconcept of the system is well suited for typical classroom use where aparticu lar lesson can be more effectively presented by simultaneousaudio and visual means.

Referring to FIG. 4, the tape recorder 24 is provided with two separatetape tracks schematically represented at 36 and 38. Track 38 is adaptedto carry the audio, and track 36 is adapted to carry the signals bywhich the memory of the system is actuated. These signals can be placedon track 36 in any suitable known manner, for example, by an oscillator40, and are in the form of tones, which may or may not be at the samefrequency, as will be later discussed. The signals are placed on track36 so as to synchronize the visual display with the narrative carried onthe audio track 38. Separate playback heads 42 and 44 are provided, withamplifier 46 amplifying the audio signal received from the reproducinghead 44 for application to the speakers 18. The amplifier 48 comprises arecording amplifier associated with a microphone 50. Separate recordingheads 52 and 54 are preferably provided for preparing the tape, in knownmanner, head 54 being connected to the recording amplifier 48 and head52 receiving keying or cue signals from the oscillator 40.

Although the preferred embodiment of the invention em ploys a two-trackmagnetic tape recorder as described, it will be apparent that comparablerecording equipment can alternatively be used. For example, a disc orrecord having two channels could be used to carry synchronously theaudio and cue signals for the visual display. A further alternative isto employ a single track tape where the cue signal is impressed on theaudio presentation. The important characteristic of the recording meansis that it effects in part the synchronization between the audio andvisual presentation.

Referring now to FIG. 2, the system of the present invention is showntherein in schematic diagram form. As above described, the audio circuitcomprises tape recorder 24, amplifier 46, and the speakers 18. Referringto the signal or control circuit, the tones carried by the signal trackof the tape recorder are channelled to an amplifier and shaper 60, withthe signal emanating from the amplifier and shaper 60 being fed in onedirection through pulse generator 62 and counter 64 to memory units 66and 68, with the amplified signal also leading to the memory unit 66selectively through filter 70 and register 72, or to memory unit 68through filter 74 and register 76.

The elements just described per se form no part of the presentinvention, and are essentially readily available commercial items. Forexample, the amplifier and shaper 60 functions to shape the signal andproduces the pulse, and comprises a commercially available band passfilter and an amplifier. The pulse generator 62 can be purchased fromFairchild Semiconductor, Mountain View, Calif, with this part beingidentified as Fairchild No. 960I. Similarly, the counter 64 isidentified by Fairchild Semiconductor as part No. 7493, and the memoryunits 66 and 68 are also items sold by Fairchild and identified by No.3501. The filter 70 likewise is a commercial item readily available tothose skilled in the art. The re gister 72 is a product of FairchildSemiconductor indentified by part No. 9001. The same applies to register76, and filter $4 is a conventional component like filter 70.

The amplified signal is also sent through enable unit 78 to decoder 80.The output of the memory units 66 and 68, whichever is selected, isdirected to decoder 80, with the decoded signal selectively actuatingthe lamps commonly designated at 82 housed within the display panel I4and associated with each letter or symbol on the display panel, as abovedescribed. The output signal from the decoder passes through a series ofSCR drivers schematically shown at 84, before passage to the selectedlamp 82 for lighting the same. In known manner, the SCR driversfunction, when triggered, is to provide an output signal to the lamps.

The components mentioned in the preceeding paragraph likewise do not perse form part of the present invention. The decoder can be purchased fromFairchild Semiconductor, and is identified as part No. 9311. Althoughthe enable circuit 78 can be separately constructed and integrated intothe circuit, it preferably is supplied as part of the decoder 80. TheSCR drivers 84 are readily available from numerous suppliers, and can bepurchased from General Electric, for example, by part No. CI06BI.

It will be noted that two memory units 66 and 68 are shown in the FIG. 2diagram. The number of memory units actually employed in the memorysystem depends upon the particular lesson or lessons. A lesson which isrelatively short, thus requiring relatively fewer cue signals, willcorrespondingly require a memory of somewhat smaller capacity. On theother hand, where the lesson is relatively long, numerous memory unitsof the type shown at 66 and 68 may be required to provide the requiredmemory capacity. It will thus be understood that, for a memory circuitof relatively large capacity, the components and arrangement thereof ofsuch larger circuit would be essentially duplicative of those shown inFIG. 2.

Generally described, the memory circuit of the present inventionoperates as follows. The first tone carried by the signal track 36 ofthe recorder 24 is at a predetermined frequency and functions at thebeginning of the lesson to reset the counter 64 and to select oneparticular memory while at the same time disabling other memories whichmay comprise the total memory circuit. For example, if the system isprogrammed to carry five separate and distinct lessons, these lessonsmay be distinguished one from the other in the memory circuit by thefrequency of the tone carried by the signal track of the magnetic tapeat the beginning of the lesson chosen. Once the lesson is chosen, thefrequency of the tone may vary within wide limits, outside the actuatingfrequencies of the selected and the disabled memories, to sequence orstep the counter, interrogate the memory unit chosen and to actuate insequenced manner the display panel 14.

The memory devices are chosen or disabled by means of filter 70, 74 etc.Each filter is designed to pass a signal of a predetermined frequency,and to block passage of signals of other frequencies. For example, toactuate memory 66, a tone of the operating frequency of the filter 70associated with such memory is fed to such filter, and then to theregister 72 to enable memory unit 66 associated therewith. The remainingfilters, which are designed for different frequencies, do not pass thesignal tone, so as to in effect disable the other memories.

Once the particular memory is chosen, each succeeding tone burst iscarried on the signal track 36 at a frequency different than thefrequency of the initial tone, steps or sequences the counter 64 whichin turn sequentially interrogates the selected memory 66 or 68, each ofwhich is preprogrammed to provide in sequence the letters or symbols insynchronization with the narrative carried on the audio tape track 38.

The memory output signal is directed to the decoder 80 from which itpasses through the SCR driver unit 84 to the selected lamp 82.

As previously noted, the recorder 24 comprises magnetic playback andrecording heads 42, 44 and 52, 54, respectively, which are schematicallyshown in FIG. 4. Oscillator 40 is capable of providing tones of anyparticular frequency in well known manner. The oscillator 40 is actuatedby pushbutton 90 for application to the recording head 52 therebyprogramming the signal track 36 of the tape. The audio and signal tracksare preferably programmed simultaneously, with pushbutton 90 beingdepressed to synchronize the signal with the audio portion of thelesson. The memory is selected by the frequency of the tone firstappearing on the signal track, with subsequent signal tones not beingcritical to frequency consideration other than to be outside thefrequency tones which actuate the selected or disabled memories. Theduration of the tone on the signal track 36 controls the interval oflighting of the lamps 82, which controlled and variable durationprovides an important teaching technique.

When switching from one frequency tone to another, as controlled byoscillator 40, a different memory 66 or 68 will be selected through theassociated filter element, and counter 64 will be reset to interrogatethe memory from an initial condition.

The amplifier and shaper circuit 60 is of conventional design and servesmerely to exclude variations in the signal and provide a suitable signalfor application to the pulse generator 62, filters 70, 74 and enablecircuit 78.

Filters 70 and 74 comprise a vibrating reed type filter characterized byextremely high selectivity and which may provide a plurality ofseparateoutput channels in an extremely small package suitable for applicationin portable apparatus of this type.

Registers 72, 76 may comprise independent flip-flop units and areconsidered triggered to the on" state when an appropriate tone has beenreceived through the respective filters 70, 74. The outputs of theregisters 72, 76 provide a conditioning signal on lines 94, 96respectively, each line being connected to a memory unit 66 or 68, thecounter 64 for reset purposes, and the other registers, not activated bythe tone, also for reset purposes. The conditioning signals on lines 94,96 enable the respective memories 66, 68 such that because of theparallel input and output connections of the memories, only one willprovide a utilizable output signal for application to decoder 80. Itwill be noted that subsequent tone bursts should not be of the samefrequency, which condition would cause constant resetting of the counter64. With this limitation, succeeding tones on the signal track 36 of thetape may be of other selected frequencies for stepping the counter 64.Pulse generator 62 is a conventional circuit which is suitable toconvert the tone burst from the amplifier and shaper circuit 60 into asingle pulse for application to the counter 64.

Most of the circuit components are of well-known design and need not bedescribed in detail for a full understanding of the invention. Thus,counter 64 may be a conventional flipflop type counter providing anoutput in standard binary code on seven output lines indicated generallyat 98, reference being made to FIG. 3. The single count change of thecounter 64 occurs from the application of a pulse from the generator 62,while the counter 64 is reset to its initial condition by receipt ofsignals from lines 94 and 96. Similarly, the decoder 80 is of well-knowndesign comprising a logic circuit to decode a binary code applied onfive input lines indicated generally at 100 representing the output ofeither memory circuit 66, 68 and activating one of the output linesindicated generally at 102 from the decoder, Fig. 2, in this instance,consisting of 32 separate lines representing the possible combinationsof the input to the SCR drivers. The SCR drivers 83 comprise individualsilicon controlled rectifiers, one for each output line 102 andcorresponding indicator lamp 82, with each SCR being energized by thesignal applied at the lines 102 to the gate electrode of the SCR andbeing commutated by an AC power source (not shown) for energizing thelamps 82. Thus, when memory 66, for example, is selected by means of anappropriate tone passed through filter 70 to condition register 72,succeeding tone bursts will step counter 64 through its count capacityto interrogate memory 66 and sequentially energize lamps 82. The time ofenergization of lamp 82 is determined by the length of the tone burst onthe tape as enable circuit 78 provides a signal on line 104 for allowingdecoder to energize a lamp so long as the tone is present. The absenceof a signal on line 104 inhibits the output of the decoder 80 and thusprecludes actuation of a lamp 82.

Memory units 66, 68 are preferably read-only memories, programmed duringfabrication to provide predetermined information. Memory 66 is shown ingreater detail in FIG. 3 in block diagram form and comprises a 32 by 32bit matrix which is subdivided into eight 32 by four bit sub-matrices ofwhich only five are used in this application and are indicated byreference numerals 106-110. Each sub-matrix 106-110 is an independentread-only memory with common addressing inputs comprising 32 horizontalrows indicated at 112 and four vertical columns indicated generally at114. By means of a decoding circuit 116 contained within the memory 66the code presented on lines 98 is converted to select one of the rows112 and one of the columns 114 thereby addressing one bit position ineach sub-matrix 106-110 where each is located at the interception of thehorizontal and vertical lines. Each sub-matrix 106-110 is provided witha single output connection indicated at 120-124 all of which areconnected to or comprise the output lines applied to decoder 80. Thus,the output on connection 120, for example, is one of I28 bits containedwithin sub-matrix 106 and selected by lines 112, 114. Therefore a fivebit output word is supplied to decoder 80 for conversion to energizationofa single line 102 and a single indicator lamp 82.

It will be apparent to those skilled in the art that this preprogrammedform of memory is eminently suitable for application in a system where aprogram of instruction must be developed and supplied to a plurality oflocations. Other types of memories could be utilized as well wherein itmay be desired to have the versatility of varying the stored program,but significant additional circuitry would be required and the economiesof this system would then not be realized.

It will thus be seen that the objects of the invention have beenrealized. A synchronized audio-visual system has been provided which isentirely self-contained within the housing mounting the visual display.The lesson or lessons are programmed on one or more memory storage unitsthat are selectively energized by the signal track of the recorder by asignal tone of a selected frequency. Except for the initial tone, whichactuates a particular memory and disables the other memories, eachmemory can be sequenced and interrogated without a code, which is adistinct advantage in programming the lesson or lessons. The system canbe conditioned for operation simply by connecting the power cord to awall outlet, and is reliable and substantially free of maintenanceproblems.

I claim:

1. An audio-visual instructional system comprising reproducing means forproviding audio and control signals representative of audio and controlfunctions, a memory unit composed of a plurality of storage devices eachcontaining a predetermined program of information and adapted to presentsuch program in sequential order, first means responsive to said audiosignals for providing an audio output, second means responsive to saidcontrol signals for electronically sequencing and interrogating saidmemory unit, a plurality of filters each of which is designed to pass asignal of a predetermined frequency for exclusively selecting one ofsaid storage devices, means for synchronizing such audio output and suchmemory interrogation, and means responsive to said memory unit forvisually displaying the program stored therein thereby to provide asimultaneous audio and visual presentation.

2. The system of claim 1 wherein said reproducing means comprises amagnetic tape recorder having separate audio and signal tracks.

3. The system of claim 1, wherein said second means comprises a counterunit for sequentially stepping said memory unit.

4. The system of claim 1 wherein said visual display means comprises ahousing having a front panel provided with pictorial representations ofthe subject-matter forming part of said program.

5. The system of claim 4 wherein all of the system components arecontained within said housing.

6. The system of claim 1 wherein said control signals are of variableduration and said display means is responsive to said control signals tovary the interval of display.

7. An audio visual instructional system comprising reproducing meansproviding audio and control signals representative of audio and controlfunctions, a plurality of memory units each of which contains apredetermined program and is adapted to present such program insequential order, means responsive to the said audio signals forproviding an audio output, means responsive to said control signals forexclusively selecting one of said memory units and disabling the others,means for electronically sequencing and interrogating said selectedmemory unit, means for synchronizing such audio output and such memoryinterrogation, and means responsive to said selected memory unit forvisually displaying the program stored therein thereby to provide asimultaneous audio and visual presentation.

8. The system of claim 7 wherein said means for exclusively selectingone of said memory units comprises a plurality of filters each of whichis designed to pass a signal of a predetermined frequency.

9. The system of claim 7 wherein said reproducing means comprises amagnetic tape recorder having separate audio and signal tracks.

10. The system of claim 7 wherein said visual display means comprises ahousing having a front panel provided with pictorial representations ofthe subject matter forming part of said selected program, means withinsaid housing for illuminating said representations, said illuminatingmeans being actuated by said memory device synchronously with said audiooutput.

1]. The system of claim 7 wherein said means responsive to said controlsignals comprises a counter for sequencing said selected memory unit,said selected memory unit being interrogated in response to suchsequencing to supply an output signal to a decoder means, said decodermeans converting said output signal and passing the converted signal toilluminating means for illuminating a pictorial representation on saidvisual display means synchronously with an audio presentation.

[2. An audio visual instructional system comprising a tape recorderhaving dual record and playback channels for providing simultaneousaudio signals and control signals,

a display panel in the form of a replica of a keyboard instrument andcontaining letters and symbols representing such keyboard,

a read-only memory programmed in predetermined codes,

an array of indicator lamps arranged in a configuration coincidentalwith the letters or symbols of said replica keyboard, said array adaptedto display the converted code of said memory as discrete indications,

a decoder for decoding each code of said memory to actuation of a singlelamp in said array, said decoder being operative in response to acontrol signal of said tape recorder, and

a counter connected to said memory for selecting the codes from saidmemory in a predetermined sequence, said counter being responsive to acontrol signal of said tape recorder, said control signals comprisingtone bursts of preselected duration for sequencing said counter and foractuating said decoder and thus a single lamp in said array for suchpreselected durations. I 13. The system of claim 12 wherein said memorycomprises a plurality of memory units, each containing predeterminedcodes, said system connected in parallel, and further including tonefilters associated with each of said memory units for energizing sameand for resetting said counter in response to the different tone controlsignals.

14. The system of claim 13 wherein each of said tone filters includes aregister for recording the first burst of tone of a preselectedfrequency, said register being operative to reset said counter andmaintain said associated memory unit in a read-out condition.

15. The system of claim 14 wherein said counter is adapted to provide asequence of output signals in binary code and said memory units comprisea decoding portion which decodes said binary code for selectingindividual row and column matrix lines in a plurality of submatrices ofsaid memory units to provide an output signal in binary code format.

16. The system as set forth in claim 15 wherein said decoder is adaptedto decode binary code to selection of one of a plurality of lines andincludes an enable circuit responsive to the length of tone burst of thecontrol signal whose function is to enable the output of the decoder.

17. The system as set forth in claim 16 wherein said memory units areread-only storage units having a predetermined code pattern storedtherein during fabrication.

18. The system as set forth in claim 17 further including an SCR drivercircuit for each indicator lamp of said array, the SCR of each circuitbeing triggered from a separate output line of said decoder toilluminate the respective lamp, with no more than one SCR beingtriggered at one time, and said circuits being energized by an AC sourceof power commutation of the last triggered SCR occurs in each cycle toextinguish the lamp in the absence of an output from said decoder.

1. An audio-visual instructional system comprising reproducing means forproviding audio and control signals representative of audio and controlfunctions, a memory unit composed of a plurality of storage devices eachcontaining a predetermined program of information and adapted to presentsuch program in sequential order, first means responsive to said audiosignals for providing an audio output, second means responsive to saidcontrol signals for electronically sequencing and interrogating saidmemory unit, a plurality of filters each of which is designed to pass asignal of a predetermined frequency for exclusively selecting one ofsaid storage devices, means for synchronizing such audio output and suchmemory interrogation, and means responsive to said memory unit forvisually displaying the program stored therein thereby to provide asimultaneous audio and visual presentation.
 2. The system of claim 1wherein said reproducing means comprises a magnetic tape recorder havingseparate audio and signal tracks.
 3. The system of claim 1, wherein saidsecond means comprises a counter unit for sequentially stepping saidmemory unit.
 4. The system of claim 1 wherein said visual display meanscomprises a housing having a front panel provided with pictorialrepresentations of the subject-matter forming part of said program. 5.The system of claim 4 wherein all of the system components are containedwithin said housing.
 6. The system of claim 1 wherein said controlsignals are of variable duration and said display means is responsive tosaid control signals to vary the interval of display.
 7. An audio visualinstructional system comprising reproducing means providing audio andcontrol signals representative of audio and control functions, aplurality of memory units each of which contains a predetermined programand is adapted to present such program in sequential order, meansresponsive to the said audio signals for providing an audio output,means responsive to said control signals for exclusively selecting oneof said memory units and disabling the others, means for electronicallysequencing and interrogating said selected memory unit, means forsynchronizing such audio output and such memory interrogation, and meansresponsive to said selected memory unit for visually displaying theprogram stored therein thereby to provide a simultaneous audio andvisual presentation.
 8. The system of claim 7 wherein said means forexclusively selecting one of said memory units comprises a plurality offilters each of which is designed to pass a signal of a predeterminedfrequency.
 9. The system of claim 7 wherein said reproducing meanscomprises a magnetic tape recorder having separate audio and signaltracks.
 10. The system of claim 7 wherein said Visual display meanscomprises a housing having a front panel provided with pictorialrepresentations of the subject matter forming part of said selectedprogram, means within said housing for illuminating saidrepresentations, said illuminating means being actuated by said memorydevice synchronously with said audio output.
 11. The system of claim 7wherein said means responsive to said control signals comprises acounter for sequencing said selected memory unit, said selected memoryunit being interrogated in response to such sequencing to supply anoutput signal to a decoder means, said decoder means converting saidoutput signal and passing the converted signal to illuminating means forilluminating a pictorial representation on said visual display meanssynchronously with an audio presentation.
 12. An audio visualinstructional system comprising a tape recorder having dual record andplayback channels for providing simultaneous audio signals and controlsignals, a display panel in the form of a replica of a keyboardinstrument and containing letters and symbols representing suchkeyboard, a read-only memory programmed in predetermined codes, an arrayof indicator lamps arranged in a configuration coincidental with theletters or symbols of said replica keyboard, said array adapted todisplay the converted code of said memory as discrete indications, adecoder for decoding each code of said memory to actuation of a singlelamp in said array, said decoder being operative in response to acontrol signal of said tape recorder, and a counter connected to saidmemory for selecting the codes from said memory in a predeterminedsequence, said counter being responsive to a control signal of said taperecorder, said control signals comprising tone bursts of preselectedduration for sequencing said counter and for actuating said decoder andthus a single lamp in said array for such preselected durations.
 13. Thesystem of claim 12 wherein said memory comprises a plurality of memoryunits, each containing predetermined codes, said system connected inparallel, and further including tone filters associated with each ofsaid memory units for energizing same and for resetting said counter inresponse to the different tone control signals.
 14. The system of claim13 wherein each of said tone filters includes a register for recordingthe first burst of tone of a preselected frequency, said register beingoperative to reset said counter and maintain said associated memory unitin a read-out condition.
 15. The system of claim 14 wherein said counteris adapted to provide a sequence of output signals in binary code andsaid memory units comprise a decoding portion which decodes said binarycode for selecting individual row and column matrix lines in a pluralityof sub-matrices of said memory units to provide an output signal inbinary code format.
 16. The system as set forth in claim 15 wherein saiddecoder is adapted to decode binary code to selection of one of aplurality of lines and includes an enable circuit responsive to thelength of tone burst of the control signal whose function is to enablethe output of the decoder.
 17. The system as set forth in claim 16wherein said memory units are read-only storage units having apredetermined code pattern stored therein during fabrication.
 18. Thesystem as set forth in claim 17 further including an SCR driver circuitfor each indicator lamp of said array, the SCR of each circuit beingtriggered from a separate output line of said decoder to illuminate therespective lamp, with no more than one SCR being triggered at one time,and said circuits being energized by an AC source of power commutationof the last triggered SCR occurs in each cycle to extinguish the lamp inthe absence of an output from said decoder.